The bilateral advantage refers to a phenomenon in which performance is enhanced for visual information that is processed from both visual hemifields rather than a single hemifield. Alvarez and Cavanagh (2005) provided a compelling demonstration of the bilateral advantage in a multiple object tracking task in which there was an apparent doubling of capacity when items were tracked bilaterally instead of unilaterally, suggesting independent resources for tracking in the two hemispheres. We reported last year that working memory (WM) for orientations also showed a reliable bilateral advantage. We are aware, however, of several studies that have failed to find a bilateral advantage for color WM, consistent with claims that the effect may relate to the efficiency of spatial selection per se (e.g., Alvarez and Cavanagh, 2005; Delvenne, 2005). To provide a rigorous comparison of how the bilateral presentations affect orientation and color WM, we measured the effect in a within-subject design in which subjects stored one of the two features, or both features from the same set of stimuli. Preliminary results suggest a selective bilateral advantage for orientation. The results will be discussed in the context of feature-based versus object-based models of forgetting in visual WM.